Overjacket for molds



1933- F. w. HAMEL 1,921,671

OVERJACKET FOR MOLDS Original Filed March 24, 1930 INVENTOR.

BY Jram 14/ Patented Aug. 8, 1933 v UNITED- STATES OVERJAOKET FOR MOLDS Frank W. Hamel, Detroit, Mich.

Substitute for application Serial No. 438,471, March 24, 1930. This application August 31, 1932. Serial No. 631,255 I 2 Claims.

This invention relates to overjackets for molds, such as are engageable with a mold after removal of a flask therefrom to prevent yielding, expanding, or cracking of the mold, in its subsequent use, and is a substitute for an application filed. March 24, 1930, under Serial No. 438,471.

Overjackets of the described. character are commonly employed to release a flask for further use after formation of a mold therein. As heretofore constructed, such overjackets have consisted of side and end walls connected substan-.

tially rigidly, and in the absence of extreme care in applying the same, there has resulted more or less relative shifting'of the cope and drag portions of the mold, and resultant inaccuracy in the casting. Also, rigid overjackets have proven troublesome in applying same to molds slightly varying from a rectangular contour due to flask imperfections, the rigid overjacket in such a case failing to strictly conform to the mold, and tending to disturb the latter.

An object of the present invention is to provide an overjacket having separately formed walls, connected so as to afford them a slight relative movement to effect their complete c0n formance to any mold approximating said jacket, in shape and size. V

Another object is to provide an overjacket for molds, the walls of which will be free to inclividually contract and expand and consequently may withstand the hightemperatures and extreme variations of temperature that are incident to the use of such an overjacket;

These and various other objects the invention attains by the construction hereinafter described, and'illustrated in the accompanying drawing:

Fig. l-is a plan view of the improved over jacket. v j V r Fig, 2 is a cross sectional view thereof, taken upon the line 2--2 of Fig. 1.

. Fig. 3 is a perspective view of a corner portion of said overjacket. V r

Fig. '4 is a fragmentary plan view, partiallyin section of a corner of the overjacket showing, with some exaggeration, how the walls may conform to an irregular mold.

In these views, the reference characterl designates the separately formed side and. end walls of a substantially rectangular frame, the same being preferably metallic and either cast or drop forged. The walls meeting at each corner of said frame areconnected by a single fastening, preferably established by a bolt 2 and nut 3, and to facilitate this connection, the walls are each flanged c0- extensively with their ends at substantially fortyfive degrees to said walls, as indicated at 4, the bolts 2 engaging said flanges preferably mid-way between their upper and lower edges.

Each of said walls is formed uponits exterior face with a pair of acutely divergent reinforcing ribs 5 intersecting substantially mid-way between the ends of such wall, and there'is furthermore preferably formed in each wall a plurality of perforations fi facilitating the escape of gases and heated air from the mold, during pouring. The,

ribs' 5 of each wall preferably extend between the flanges 4 thereof. The opposite walls have a slight downward flare to correspond to that of the mold sides, the flanges 4 being relatively inclined to the main planes of the walls 1 to establish such flare. The nuts 3 may be tightened or loosened upon the bolts 2 to afford such play between the meeting walls as may be required to fully conform said Walls to a given mold. 1

By thus providing for a limitedplay between" the meeting walls of an overjacket, the latter may adjust itself accurately to slight variations in dif-' ferent molds, and the percentage'of loss from defective castings due to disturbance of the mold by the overjacket may be greatly reduced. The construction avoids necessityfor machine operations, excepting the simple one of drilling the flanges 4 to take the bolts 2. The holes receiving said bolts are sufficiently oversized to permit considerable angular play between the joined walls. I

I While itis apparent that the invention is well calculated to adequately fulfill the objects and I advantages primarily stated, it is to be understood that the invention is susceptible to variation, modification and change withinthe spirit and scope of the subjoined claims.

WhatI claim is: l 1. An overjacket for molds comprising opposed side and opposed end walls forming a substantially rectangular frame, each of said walls being integrally formed with flanges outwardly projecting in a substantially diagonal relation to said rectangular frame, the opposed walls being down- Wardly divergent and said flanges being substantially vertical, said flanges having substantially the full height of said walls, the adjacent flanges of adjoining walls being formed with registered openings, and a connecting member mounted loosely in said openings of each pair of adjacent I flanges, maintaining the adjacent relation of said flanges and affording the connected walls ade to conform 

